The Mortal Instruments: The City of Outcasts
by Lianna.Drake
Summary: Edited all chapters! Sebastian Morgenstern's life is changed in a drastic way when Serena Henning saves his life. Now he is forced to follow her in her travels as a healer witch around the world. Because without the potion she created, the heavenly fire in his veins will consume him and he can't let that happen. He hasn't accomplished his goals. Starts at the epilogue of TCoLS.
1. Change

**Author's note: I've finished chapter one. Yay to small victories! This is the first story I have ever posted, so I am very nervous about how you all are going to like it (or not like it). I've had this story in my head for a while now, but never "got it down on paper" so to speak. I think there are some improvements to be made (this is my second draft) and I intend on doing more editing in the future. If anyone has suggestions, I'm open to constructive criticism!**

 **DISCLAIMER: I do not own The Mortal Instruments or its characters.**

* * *

At the age of eight, Serena's mother decided to pay a visit the new neighbor who had just moved to town. She was a middle-aged woman and her dress was exactly as Serena imagined a hermit cat lady would look. Her glasses were thick and magnified her eyes to twice their size and her hair was a mass of thick curls the color of ashes. Admittedly, Mrs. Pendle didn't have any cats and she was quite friendly. When introduced to Serena, the keen-eyed woman half crouched with her hands on her knees and examined the shy little girl clutching her mother's hand. "Well, aren't you just the most adorable little thing. Why, I bet when you grow up, all the boys will be falling at your feet." Serena couldn't help but giggle, though her new neighbor turned out to be right.

Now, at the age of 17, Serena was positively gorgeous. Her hair was raven black, traveling down to the small of her back. Her skin was lightly tanned and unblemished. Only slightly above average height, her figure was slim with curves in all the right places. Her lips were full, lush and seemed quick to curve into a smile. But it was her eyes that were the most striking feature: long lashes framing violet irises that changed with her mood.

Yes, boys did fall at her feet, often vying for her attention, but Serena doubted that Mrs. Pendle could have anticipated that one day a boy would literally fall – from the sky – at her feet. Yet that is exactly what happened one night while Serena was out in the forest that surrounded her current lodgings. She was sitting in the middle of a clearing, on the stump of a tree long since cut down. She spent hours gazing up at the night sky fantasizing about the future. Wondering what it could have been like if things had been different. She was gathering her things – a book, a plate with a half-eaten sandwich, a bottle of water, and a camera – into a picnic basket, when the boy dropped with a loud thud directly in front of her.

"AAAHHH." She jumped so violently she almost fell off the stump. Leaping to her feet, she seized the leather bound book out of the basket, gripping it with both hands and pulled it back over her shoulder ready to swing it forward….but the boy didn't move. He lay on his side; his back to her, so she could not see his face. Serena stood - frozen, anxious - looking for any sign of movement, of attack…still nothing.

Hesitantly, Serena relaxed her grip on her makeshift weapon, and slowly lowered it back into the basket. Crouching beside him, Serena tentatively reached out to roll the boy, apparently unconscious, onto his back and discovered there was a pool of dark red forming on his chest. Frantically, she searched for a wound. She couldn't find any tear in his clothing, so she undid his shirt. There! In the center of his chest, a large gash approximately four inches long. Very gently, she used his shirt to wipe away the blood to get a better look at it. She frowned. It was a deep stab wound, she noted with worry.

She glanced around the clearing, contemplating what to do. He needed help fast, no question. He was too heavy for her to carry on her own. She could leave him and seek help…..but there was no one close enough; he would be dead before she got back. She let out a shaky breath. _Only one option then,_ she thought. She didn't like it. She had never taken another person with her before and she wasn't certain that with his wounds he would survive it. _No choice_ , she reminded herself. Leaning down, she slipped her arms under his shoulders and lifted him up so his head was cradled on her shoulder, his forehead resting against her neck. She touched her left hand and they vanished.

* * *

They materialized in her house, in the kitchen by the island. Serena gentle lowered the boy to the floor and sprung up, tossing the picnic basket off to the side, to fetch her medicine kit from a cabinet under the kitchen counter. Kneeling down beside the boy again Serena opened the kit and selected one of the vials. Unscrewing the dropper, Serena pushed down on his chin to open his mouth. She squeezed three drops onto his tongue. The effect was immediate. The blood pumping out of his chest wound slowed. Swiftly, she replaced the vial and pulled out a length of bandage. She was about to press the cloth to the wound when she saw what she didn't in the dark.

Mixed in and swirling in the blood was an orange liquid. Serena snatched an empty jar from the kit and a fresh dropper. Collecting some of the blood and mystery liquid in the jar Serena held it up to the light looking up at is from the bottom. _It looks like…liquid fire._ As Serena examined it, she could see the blood in the jar was slowly being consumed by the orange substance. With a frown Serena set the jar aside. _Fatal wound first, Rena._ Picking out yet another jar, this one filled with a purple fluid, Serena uncorked it. After inserting a tube down into the wound and attaching a small funnel, she slowly tipped the contents of the jar into the funnel letting it trickle down the tube while slowly pulling the tube out as she poured. When the tube was pulled out completely Serena cleaned and bandaged the wound.

Serena didn't bother to stitch him up. The first potion she gave him slowed his blood flow. The second would heal and close the stab wound in about a half hour. Now that the boy was in no immediate danger of dying, Serena settle back against the kitchen island cabinets. She picked up the jar of mystery liquid she had set aside, thinking. _Liquid fire. A stab wound in the chest. A fire sword?_ The description sounded familiar. Serena tapped her middle finger on the side of the jar. _If it's consuming his blood…._

Now that she had a light to go by, Serena pulled a flat bottomed round crystal from her pocket and placed it on the boy's shoulder. She watched as a cloud of color bloomed from the center of the clear crystal and settle into three sections of color: equal parts tan and white, but the dominant color was black. It took up three quarters of the crystal's surface and was mixing with the tan and white. It wasn't supposed to be there. Translation: he was part human and part angel, but his body was corrupted by demon blood. _Bingo. So not a liquid fire. A holy fire that is consuming him from the inside out…._ Memory sparked. One of her mentor's books spoke of a holy sword, given to the archangel, Michael, which cleansed evil from those that were struck by it. _He's being cleansed._ Looking at the jar again, there was no trace of the blood that had been mixed in with the substance. There wasn't enough good left. The heavenly fire would surely kill him.

Serena stood and rushed about the house in a flurry of pots, jars and bowls. Gathering all of it on the kitchen island Serena surveyed the paraphernalia with her arms out, gripping the edge of the counter. She closed her eyes and steadied her breathing, letting her instincts guide her hands. Without looking at the paper in front of her, she began to write. She scrawled the names of several ingredients and their precise amounts, how to combine them and in what form.

When her hand stilled, she looked down at the results. Serena frowned, annoyed. _This is no good. In these amounts half the ingredients in this potion will kill him._ Setting the recipe above a fresh sheet of paper, she tried again. _Hmmm, maybe not in one dose then. Spread it out over time._ Her next recipe involved the same ingredients in smaller, non-lethal doses. Serena smiled, satisfied… for a moment. This potion would stop the heavenly fire from killing him, but it wouldn't stop the alteration. There was no telling what state he would be in when the heavenly fire burned itself out. And it would burn out as it combines with the potion. She might end up making things worse for him. _Still, I can't just let him die._ So, Serena set to work mixing her new medicine and when she finished made the boy drink it hoping she wasn't going to screw this up.

* * *

Now, standing over the boy still unconscious on her kitchen floor, Serena contemplated how she was going to move him to the bed in her infirmary. Once again she was presented with the dilemma of how her weak and girly self was supposed to move a grown boy; her talent in moving objects with magic was nil. Serena gave a heavy sigh. She didn't want to bring anyone into this yet, but…

Serena strode over to her bag and pulled out a basic cell phone. She flipped it open, pressed the number three on her speed dial, and waited. He picked up on the fourth ring.

"…Hello?" The voice on the other end sounded groggy and slightly annoyed.

"Hey. It's me. I need you to come here and help me." Serena didn't waste time getting to the point.

"Do know what time it is?" The grogginess was gone, the annoyance doubled.

"Yes." Serena replied cheerfully. " _I'm_ still awake."

"Smart ass."

"Just get over here and help me."

There was silence on the other end and Serena could feel the suspicion coming through the phone. "Tell me what you want first."

Serena rolled her eyes. "I promise this isn't like the last time when I asked you to help harvest the Veneullium Weed, you wuss."

"You didn't tell me that damn weed had hallucinogenic pollen. I was on a psychedelic hippy high for four days!" He raged.

"I told you to handle it delicately." Serena replied dismissively.

There was a scoff on the other end of the line. "You could have elaborated a little."

"Whatever. I just need you to move a patient for me."

"'Move a patient'? When did you get a patient?"

"Half an hour ago." Serena inspected the fingernails on her right hand.

"You're finding patients in the middle of the night now?"

"No. I was stargazing and he almost, literally, fell into my lap." Serena explained. "Now, are you going to help or not?"

"Hmph…fine." Then, he hung up.

Serena snapped her phone shut and placed it on the kitchen counter. While she waited, she put the jars of ingredients back in their cabinets and turned down a bed at the far end of the infirmary. Next, she hauled out some cleaning supplies; she put them against the wall, keeping a bucket and some mild soap, and filled the bucket with the soap and warm water. Setting the bucket down next to the boy, Serena reached over him into her bag and pulled out a clean handkerchief.

With her patient stable, for now, Serena finally took the time to really look at him. His black trousers and boots were splattered with mud and grass. When she removed his boots bits of gravel fell out. On each wrist, he had hammered silver bracelets. Real silver from the look of it. She slipped them off and set them next to his boots. His leather tunic was a beautiful scarlet red. It was a shame it was now ruined with blood as the design must have been lovely. Intricate gold and silver runes were embroidered along the collar and cuffs. She didn't recognize the runes, but she wasn't surprised; Serena only bothered to learn about runes related to healing and defense. Serena began to undo the rest of the metal clasps that held his tunic together. Carefully she stripped the tunic off his arms and lifted him up to slide it out from under him. The hand at his back brushed against several lines of scars. Someone had whipped him and that knowledge filled Serena's healer heart with disgust and sadness. Another reminder of the cruel people in his world; a reminder no one needed nowadays. She put the blood soaked shirt with the rest of his belongings.

Dunking the cloth in the warm soapy water felt good on her cold hands. Serena wrung out the excess water and began to finish washing off the blood and dirt on his torso being careful to avoid the bandaged wound in his chest. His skin was pale, but Serena didn't think that was entirely the result of blood loss. He had an athletic build, muscular. Obviously he was quite active in his day to day life; which meant to Serena he was going to be a problem patient: active people don't like being stuck in a bed recovering. Peering at his face she could see he was quite handsome. His features were sharp and she wondered what color his eyes were. His hair wasn't platinum-blonde like she had thought at first glance, but pure white. It looked soft. Serena reached out her hand and –

KNOCK, KNOCK, KNOCK.

Serena jumped and snatched her hand back. Mentally shaking herself, Serena pushed to her feet and walked to the door. Pulling back the deadbolt and swinging it open, she gave her friend an apologetic smile. "Thanks for coming, Jenal."

On her threshold Jenal's frame filled her doorway. He was an American football coach's dream. Profile: 6' 3", broad shoulders, very strong, fast, and agile. His features were rugged, he was almost always frowning, and his most natural expression was a glare. Most people were intimidated by Jenal – until they get to know him. Despite his appearance Jenal was what people would call a 'gentle giant'. He was kind, protective, and loyal; which all of his friends found amusing since Jenal was a werewolf. Solanna, his girlfriend, liked to joke that he was his own best friend.

Right now, however, Jenal looked especially menacing with his shoulders hunched and his hands stuffed in the pockets of his brown leather jacket. His chestnut brown hair was uncombed and messy, having rolled out of bed to come here. His worn boots were caked in mud and bits of grass from trekking through the forest to reach her home.

"Yeah, yeah. Let's get this over with so I can get back to sleep." Jenal made to step into the house, but Serena put up her hand to stop him.

"Uh-uh. Wipe your shoes off first."

Jenal rolled his eyes, but did as he was told. Serena stepped back and to the side. Jenal saw the boy on the floor as he walked into the house. He stopped beside him and crouched, placing his elbows on his knees. He surveyed the mess of bloody bandages, cloth and medical instruments around the boy and whistled. "Someone did a number on him."

Serena closed and bolted the door behind Janel, then joined him. "Yes."

"You said he fell into your lap. Did he fall from a tree?" Jenal looked up at Serena.

Serena's lips twitched in a smile. "Close. But I don't think his injuries came from the fall."

Jenal nodded, carefully lifting the bandage on his chest to peek at the wound. "Looks like he was stabbed with a broadsword. Shadowhunters?"

"Maybe. I won't know until he wakes." Serena decided not to tell Jenal her patient had been stabbed with a holy sword that belonged to the archangel Michael. "Let's get him into the infirmary."

Jenal slipped his arms under the boy's shoulders and knees and gently lifted him up. "Who is he? Is he a Downworlder?" Jenal asked as he rounded the furniture of Serena's living room and turn to slide sideways through the door in the back right corner of the room. Jenal walked down the long room to the last bed, the bed Serena had prepared and put the wounded boy down as gently as he had picked him up.

"He didn't have any kind identification on him," answered Serena evasively. She covered her patient with the blankets and avoided looking at Jenal.

Jenal narrowed his eyes at Serena into a true glare. "Meaning you know who he is."

Serena glanced over at Jenal and then away. She simply said, "I have a thought."

"A thought I won't like, I'll bet." He crossed his arms over his chest.

Serena shot him a look that said 'You are being childish.' She leaned over her patient and flushed the pillow behind his head. "He is hardly dangerous in his current state."

"And when is his 'current state' going to change?" Jenal demanded.

Serena assured him, "Not for a few days, I imagine."

"I recommend shackles when the time comes."

Now it was Serena's turn to glare. She refused to restrain a patient without cause. "Thank you for your help Jenal." She injected her voice with false sweetness.

"Fine. I should know you won't listen to me anyway." Jenal made his way out of the infirmary and headed back toward the door.

Serena leaned her shoulder against the infirmary door frame. "You know, you can sleep in the guest room until morning."

Jenal unbolted the door and opened it before turning back to her. "Nah, I like the company in my bed better." With that remark he shot Serena a wicked grin, stepped outside, and swung the door shut behind him.

Smiling, Serena shook her head and turned back to her patient. Her healing potion should have closed up the wound by now, though it would still be tender. The smile slipped from Serena's face. The next day would not be kind to him. The ingredients in his medicine would be tough on most people individually. Combined together with the heavenly fire-infused blood she collected from his wound, they would be brutal. It was entirely possible he would not survive the next two days. But if she could get him through it – if she could save his life – she might be able to change the all but certain dark and bloody future this world was about to face. Because Serena had no doubt in her mind that the boy lying in her hospital bed was Jonathan Morgenstern.


	2. Girls Chase Boys

**Author's Note: Chapter 2 is here! I hope you are all liking this. I haven't gotten much feedback, but so far it's been positive. Tell me what you think! I am trying to be consistent with the first five books, but it's been awhile since I've read them. If I get something wrong, please, please tell me! In the meantime, I will continue doing what I'm doing, I guess! Cheers!**

* * *

Serena stood before the bed, staring at it in utter disbelief. It was empty. EMPTY! How was this possible? It had only been three days since he arrived in her house. There was no way he should have been conscious much less GONE! She ran her hands through her hair in frustration. She had to find him before it was too late. In less than two days he would need another dose.

She spun on her heels, marched to her lab, ripped open the cupboard where she stored the potion she needed, and stuffed the vial into her messenger bag. Stalking into the laundry, she grabbed one of the blood stained towels from three days ago and yanked out a thread from the towel. Soaked in her errant patient's blood it was perfect for tracking him down. She retrieved a flat round crystal case from her bag. Etched on the surface of the case was a rune for tracking. Serena popped open the case with her thumb, placed the thread inside, and snapped it shut again. The thread pulsed with a soft light and a vision flashed before her eyes. A city, a statue of a woman holding a torch, an old church – that wasn't a church, and in the church was a library. The vision slowly cleared and she saw her own kitchen again.

The Shadowhunter's Institute in New York. That was where he was. Serena sighed. How had he gotten half way across the world in only a few hours in his condition? She walked over to the door, but instead of leaving she opened a large cabinet just to the right of it. There were several rows of crystals in various colors, ten in each row. Between the door and the cabinet there was a panel and behind it a small hole, a slot for a single crystal to be inserted. At the moment, there was a sky blue crystal in the slot. Serena removed the crystal, picked out a slate grey one from the cabinet, and swapped the two. Pushing the grey crystal into place, the outside changed from warm summer morning to cold winter afternoon. The sound of a car horn blared from the street outside. Again, Serena sighed. She didn't really care for New York. In her experience, the people were so cynical and rude. She closed the panel, grasped the doorknob, slung her bag over her shoulder, and stepped out into the city. Shutting the door and locking it behind her, she glanced up and down the street. No one paid much attention to her and why would they? As far as they knew she had stepped out of her two story townhouse (never mind that no one has come in or out of it in two years).

She turned right and headed up the street. _What idiot wakes up after nearly dying and thinks 'Hey, I think I'll head to New York and ignore how I got in this unfamiliar house'?_ Though, the fact that the guy managed to get here on his own was a bit impressive. He had to be pretty strong. Serena frowned - she was doing that a lot lately. She knew he was strong to have survived the trauma of the last three days.

* * *

 _Serena was reclined on the bed six feet from the one her new guest occupied, reading her new book on water plants and their uses in curing skin irritation. It had been almost half a day since he arrived. Everything was progressing smoothly, though she didn't expect it to continue that way much longer. She could see the potion was taking its toll on his body; his skin was losing what little color it had, his temperature was starting to rise, and his breathing was slowly getting shallower. Since there was no telling when the worst effects of the potion would hit him, Serena rescheduled all of her appointments for the whole week to stay near him as much as possible. Jenal called her several hours after his visit at about 8:00 AM to 'make sure he hadn't woken up and butchered you', as he so charmingly put it. But, as Serena predicted, he didn't even crack open an eye that first day._

 _It was just after noon on the second day and Serena was monitoring his developing fever. She passed most of the time reading or examining his belongings. She now knew how he ended up falling into her lap; the ring on his hand was almost identical to her own - less sophisticated, but similar. Serena guessed that the house his ring was connected to was somehow lost or destroyed. He either didn't know or was in a rush to escape his attacker and forgot. Whatever the case may have been, the ring couldn't send him there, but it did find another destination. If Serena's house wasn't protected against unannounced visitors, the spell probably would have sent him there like her ring did. Instead it chose the next best thing: another ring bearer._

 _Serena did go out once. When he first appeared before her, he was wearing an empty sheath for a broadsword. She decided it would be safest to retrieve it before someone else stumbled upon it. The sword now sat in its sheath, leaning against the wall beside a chair where she put the rest of his things. They would be one of the first things he saw when he woke, in case any of it held sentimental value to him - value he likely didn't recognize on a conscious level._

 _Serena heard a cough from the other bed and looked up from her book. She threw the book down and swung her legs to the floor, rushing to his side._ Here we go _, she thought. Jonathan coughed again, ending in a gasp for breath. Sweat was collecting on his brow and Serena wiped it away with a cool cloth. Then he began to seize. Serena tossed away the cloth, grabbed his shoulder, and rolled him onto his side. The seizure lasted four minutes, after which Jonathan immediately started vomiting blood. When he finally settled, he was shivering. Serena put her hand to skin that minutes ago had been hot, but was now cold as ice. She wiped the vomit out of his mouth and laid him back down. It wasn't blood on the rag she used, but a thick black sludge. She wasn't certain if this was a good sign or a bad one. She rounded the bed and set herself to cleaning up the mess, being sure to collect some in a jar to examine later in her lab upstairs. When she finished she pulled the blanket off her bed and draped it over him. Laying her hand on his shoulder, she squeezed gently. "Round one."_

 _Jonathan's attacks continued, at random intervals, into the evening and through the night. Each one lasted longer - the longest she clocked at ten minutes. Serena made sure to keep him hydrated and fed him soft food, since he couldn't eat himself. She felt bad forcing him to eat and drink when she knew he was going to throw it up later, but his body needed whatever strength and nutrients he could get from it. It wasn't until dawn that the attacks started to slow down; the time between them grew longer and their duration shorter. By the afternoon the seizures had stopped and the vomiting stopped soon after that. His fever and chills broke late that same evening and Serena was hopeful that the worst was finally over. They both got some rest that night._

* * *

He spent the next day sleeping, much to Serena's relief, and this morning Serena felt it safe enough to go out shopping for essentials. When she had returned he was gone. It was vital that she find him quickly. He needed to drink her potion every two days and today was that second day.

Serena hailed a taxi. She gave the driver an address that was one block from the Institute - no reason to get needlessly close. She watched the people and the buildings as they passed by ignoring the cab driver's fleeting stares as he watched her in the rear-view mirror, trying to ascertain whether her eyes really were violet. Upon tracking her destination, Serena slapped the fare on the center compartment and climbed out of the cab. She could see the old church ahead of her. Serena leaned against the building adjacent to the church grounds and surveyed the area. No one was rushing about or yelling, so they obviously hadn't found him. She couldn't walk in; they would know her as a stranger. Serena was about try the tracking spell again when she felt something brush her leg.

At her feet a Persian cat weaved through her legs. Its yellow eyes gazed up at her with intelligence. When it knew it had her attention it trotted off down the alley between the building and the church. Serena knew when someone wanted to be followed, so she did. Rounding the corner she found the animal sitting below a fire escape ladder. Serena stopped next to it, crouched down, and scratched the cat behind the ears a few times. She then grabbed the ladder and climbed up. The first landing's walkway wrapped back around the corner then went up another level. She jogged up the stairs to the next landing and found herself not quite in-line with one of the Institute's open windows. From the tall shelf of books she could see inside, Serena guessed it was the library. Leaning on the rail, Serena could pick up two voices carried on the wind.

"She found it this afternoon."

"Just the wings?"

"Yeah…"

"How the hell did he catch an angel?!"

"Who knows? Let's just get it cleaned up. It makes me sick just thinking about it."

"Oh, lovely." Serena ran her hands through her hair. "Way to take something beautiful and make it horrifying, Jonathan." She straightened, and climbed down the fire escape. With her feet on the ground again and no sign of her feline helper, she tried tracking him again. The vision this time showed the tree line of a park. It wasn't far off - she could see the outline of the Institute on the skyline.

Serena set off again. Just as she was passing the gates of the Institute, someone walked out of them and into her. She stumbled, but managed not to fall and felt two hands reflexively grab her arm.

"I'm so sorry!" Looking at the girl who had nearly knocked her over, the first thing Serena saw was red hair and green, worried eyes. Serena's gaze flicked back to the Institute. _She must be a Shadowhunter_ , Serena thought. When their eyes met, the red-haired girl's expression changed from apologetic to surprise. She stared at Serena's bright violet eyes with curiosity.

Serena flashed her a generic smile. "Don't worry about it." She gently pulled her arm away. The girl, realizing she was holding on to her, promptly let go. Serena stepped around her and continued walking. She could feel the girl's eyes on the back of her head.

"Clary?" Serena heard another female voice call out behind her. "What are you staring at?"

"Uh….nothing." Clary responded. Serena heard footsteps walking in the opposite direction.

Entering the park, Serena walked the tree line until she came to the spot in her vision. When the wind died, she heard the faint sound of heavy breathing. She peeked around the nearest tree, and there he was on the ground, leaning against it. She knelt down next to him and his head tilted up. He was still conscious; his eyes barely open.

She peered into his face. "Thought you'd go on a trip did you? You need your medicine. Can you drink?"

His eyes fell shut and his body went limp. Serena made a face. "Ooof course, not."

She got the little bottle from her bag and let the potion trickle into his mouth while simultaneously massaging his throat to trigger his reflex to swallow. When the bottle was empty she stashed it back inside her bag and turned the ring on her hand.


	3. Rude Awakening

**DISCLAIMER: I do not own The Mortal Instruments or its characters.**

* * *

His head was pounding. His throat was dry. There was a bitter acidic taste in his mouth. Cracking open his eyes Sebastian found himself looking up at an unfamiliar ceiling and got a sense of déjà vu. As his mind cleared his memories started to come back in a groggy jumble and he remembered: he woke up here last time.

* * *

 _He was weak, confused. He remembered the fighting, the clash of weapons, and the smell of blood. His opponent was unconscious at his feet. He was about to land the final blow when a searing pain hit him in the chest. He screamed in agony and in his mind he could feel his bond with Jace unraveling. Blood was spilling from a stab wound he hadn't received, staining his red tunic a darker red. Glancing off in the direction he had last seen Jace, he briefly wondered if perhaps his sister's friends had decided that his death was worth more than Jace's life. But this didn't feel like dying. He knew what that felt like. Right now he felt like he was on fire. Sebastian called a retreat. It didn't matter. He was finished here. He would come back for Clary - and Jace too, if he was still alive. He turned the ring on his finger forgetting for only a moment that the apartment was gone and it wouldn't work. But, to his utter surprise, it did._

 _Looking around the room he guessed he was in an infirmary. It didn't look like a hospital. Was this one of the Institutions? No. He was more likely to have woken up in a cell if that were the case. Sebastian pushed himself into a sitting position and looked down at his chest. The wound was gone. All that was left was a very faint trace of a scar. He found his things beside the bed neatly washed and folded. Only his stele was missing. He swung his feet to the ground and stood slowly. He was a little unsteady but he wouldn't fall. He dressed quickly and made his way out of the room._

 _The infirmary lead out into a living area. Two cushy chairs were arranged to face a large bookshelf, a small round table with a lamp stood between them. A large area rug in warm colors covered the wood floor underneath them. To his left and at the far end of the room was a kitchen. Completely open to the living area, the counter extended along most of the wall. It stopped before a door that appeared to lead outside. An island provided more counter space and three bar stools were placed on one side. A door farther down lead into a small dining room. A table that seated four was the main piece of furniture. Across from the dining room door was a closet door. Based on the articles of clothing hanging in there Sebastian guessed that this place belonged to a woman._

 _He was quickly disappointed in his explorations after that, however. There were three doors that refused to open: the door next to the closet, the door along the back wall, and the door at the top of the stairs. Aside from the infirmary this place looked like a normal house. Sebastian decided he would come back to investigate later. Right now he needed to get back to his base of operation and recover his strength. But first, he had a message to send…_

* * *

Sebastian was back in that infirmary. He remembered being hit with a sudden wave of exhaustion and collapsing at the base of a tree in a park not far from the New York Institute. He had willed his body to move - he could not allow himself to be captured here - but it would not obey. He recalled that after some time, though he didn't know how much, a girl crouched next to him. A girl with black hair and violet eyes. Then, everything went black.

Sebastian slid his hands back to sit up. He heard a tinkling sound, then they were tugged to a stop. Looking down at his wrists he saw they were shackled to the bed frame. The shackles were not made of metal but some sort of white crystal. He lifted his arm until the few inches of chain were pulled taut and turned his wrist to inspect it. Writing was etched into the manacle around the top and bottom and along both sides of the lock. It was also etched into each link of chain.

The floorboards creaked and Sebastian's head snapped up. In the doorway stood the girl from the park. Her long black hair fell in gentle waves down her back. Her skin was pale and unblemished. She wore a beige sundress, trimmed in white with matching sandals. She carried a tray of bottles filled with of liquids and powders of various sizes and colors.

"You're awake." She gave him a gentle smile and her expression was a mixture of happiness, relief, and triumph. She walked to a counter with an overhead cabinet in the corner of the room and set the tray down. She picked out a bottle from the cabinet, filled a glass with water, and walked over to his bedside.

"Who are you, witch?" He asked curtly. Because of course she was a witch. Her violet eyes, potions, and spelled chains say she was.

"Serena Henning." She pulled the cork lid off of a jar containing what looked like herbs compressed into dime sized tablets. "Oh, before you ask, no, I will not remove the shackles. I will not have you wandering around again in your state. And don't bother trying to break them. You will stay like this until you and I have a talk about your situation."

Sebastian glared at her. The name Henning struck a chord in his memory but he couldn't place it. He mentally filed it away to be considered later. "My situation?"

"Your little adventure nearly got you killed and you didn't even know it. If you had waited before running off when you woke up I could have told you that."

Sebastian fell silent. Was this a trick or was she telling the truth? "Explain."

Serena shook her head. "First, we deal with the now. How do you feel?" She put her hand over his forehead. Sebastian pulled away slightly, unsure of whether this girl meant him good or ill. Did she know who he was or didn't she?

As if she read his mind, she rolled her eyes and chided, "Oh, would you relax? I saved your life. I'm not about to waste all of that effort by killing you the moment you wake up." Serena grabbed two pillows off of another bed. "Here, sit up a little." She helped Sebastian raise his shoulders high enough for her to stuff the pillows behind him. Now he was in a semi-reclined position.

"Does anything hurt? Or feel off?" She kept pelting questions at him.

"I have a headache." He muttered, annoyed. The urge to silence her, possibly forever, was growing.

"I thought you would." She select one of the tablets from the jar. "Open your mouth."

Sebastian stared at her like she was crazy.

Serena stared back. "You can't do it yourself. I told you the cuffs won't come off until we talk."

"Then talk." He shot back.

"Headache first."

Sebastian clenched his fists and let out an exasperated growl and did as she asked, for now. Serena placed the tablet in his mouth and brought the glass of water to his lips. He gulped down the water and tablet. The pounding pain in his head instantly vanished. Serena flashed him a bright smile. "Better?"

She obviously knew he was, so he stared at her expectantly. With an amused expression she set the glass down on the end table and dropped the lid on the jar. "What's the last thing you remember? Before waking up here, of course. Some kind of fight?"

Sebastian raised an eyebrow. "You don't know?" News of what happened at Burren should have spread like wildfire.

"Well, I've spent all of my time attending to a certain unconscious someone for the past four days. You'll have to forgive me for being a little behind on current events. I can guess most of what happened to you, though." Serena slid a chair that stood near the bed away from the wall and positioned it to face the bed. She smoothed out the back of her skirt and sat down. "You got yourself stabbed in the chest with the Archangel's holy sword and to escape the peril you tried to use your ring, but your destination was no longer accessible."

Sebastian studied her face with narrowed eyes. "How do you know about my ring?" If she was out of the touch with events as she claimed, she shouldn't -.

Serena raised her hand, palm facing away from him and wiggled her fingers. There, on her middle finger, was ring with the same writing inscribed on the band as his own. The band was silver and set with a trillion-cut sapphire. "Did you think you were the only one with a fancy, dimension shifting house?"

"This place?" he asked as his eyes flitted about the room before settling back on her. If he could free himself and get that ring from her… "Did you create it?"

"No. I inherited it from my mentor." There was a flicker of sadness in her eyes and Sebastian actually saw the color of her irises darken for a brief moment before brightening to their original rich violet. "But we are getting off topic. The more I know about what happened to you the better I can help you stay alive."

"This has something to do with my 'situation', I assume."

"Yes." Serena paused, presumably considering how she was going to phrase her next statement. Apparently she decided to go with blunt honesty because the next words out of her mouth were "You were dying. The hole in your chest was easy to heal, but the sword was imbued with heavenly fire…..Once it was in your body it got right to work purifying any evil within you and given the significant amount of demon corruption in you…. it would have killed you."

Demon corruption...so she did know. Again, it was like she read his mind. "Yes, I know who you are, Jonathan Morgenstern." She gave him a wry smile which faded into seriousness and her words came out in a rush. "Look, I've made a potion that will prevent the heavenly fire from killing you but it doesn't eliminate it and, because of the ingredients involved, the amount of the potion needed for a one time dose would kill you faster than the heavenly fire would. So we have to spread it out into smaller, frequent doses.

Which means your little jaunt yesterday nearly got you killed." She scolded him like a ten-year-old. "If I hadn't found you when I did you would be long dead by now." Sebastian recalled again the sudden exhaustion he felt yesterday. A result of the heavenly fire trying to purify him. But the biggest question on his mind right now was, "If you know who I am, why save me at all? Most of the world wants to kill me."

The room fell silent. All that was heard was the ticking of a clock in the other room. Serena dropped her gaze to her hands resting in her lap. "I thought about it. A few times since you came here. But…. I don't think I have the right to decide who deserves to die."

Sebastian scoffed at her answer. It was an idealist philosophy that would only work in an idealistic world. This world was anything but ideal. She would soon learn. But her ridiculous ideals were working in his favor. "Then give me this potion, let me go, and I'll let you go back to playing hospital."

Serena gave him a look. "I'm not a moron. The moment you get your hands on that potion you'll snap my neck. Well, I hate to break it to you, but you need me." Serena crossed her arms and gave him a superior look. "This potion needs to be made fresh each time or its effectiveness diminishes."

"I've never heard of a potion that had a shelf life." Sebastian stated in disbelief.

"It didn't even _exist_ until four days ago and we are dealing with heavenly fire. Do you really think normal rules apply?" Her tone was very matter-of-fact.

Sebastian gritted his teeth. He had no way of knowing whether this annoying woman was telling the truth or lying to protect herself. It could even be a bit of both. Putting a leash on his temper, he just wanted to get out of here. "Fine. I'll come back for it when I need it."

"Pfft. You need a dose every two days. You really want to do that back-and-forth nonsense?"

"Every…two...DAYS?!"

"That's right. Plus, I am not letting you walk out of here to continue your rampage across the world. Not while you are my responsibility, anyway. If you want that potion, you stay here and be a good boy until the heavenly fire runs its course and you no longer need it." Serena ended this declaration with a definitive nod.

Had he actually thought her ideals were working in his favor earlier? He stood corrected.


	4. The Contract

**DISCLAIMER: I do not own The Mortal Instruments or its characters.**

* * *

Jonathan's answer was swift and decisive. "No."

Serena guessed that would be his initial reply. This was where her skills in persuasion - and to be honest, manipulation - would be crucial. If her plan was going to work she needed him to agree to her terms. Serena knew she couldn't lie through her teeth and pretend she didn't care what happened to this world. He expected lies and would see through that in an instant. No, if this was going to work she would have to stick as close to the truth as possible while simultaneously eliminating any alternative avenue he might think up.

For instance, the potion _did_ appear to lose effectiveness over time. _If_ she stored it in regular glass containers instead of her special crystal containers. But she wasn't stupid enough to tell him that.

"If you want my help, you have to put a hold on your destructive tendencies until such time that you and I are no longer associated with each other. I will not enable bad behavior." She continued to talk as if she were disciplining a child who was planning nothing more than graffitiing a school and not the destruction of the world. It wasn't necessary to her plan, but she wanted to test how far she could push him with a bit of goading. She could almost see a vein pulsing in his temple. A small part of her was enjoying this.

"So, what? You don't care what I do after we part ways?" He voice dripped with sarcasm and anger.

Serena, keeping up her nonchalant attitude, casually waved away his question. "Well, I'm hardly a match for you and personally I would rather let the Clave deal with you. Also, if they find out I helped you…..they might get the wrong idea. Best they don't know I was involved in the first place."

While he digested that she continued, "All I'm asking is that you don't make me an accessory to murder or destruction of property. Think of it as you mercifully granting everyone three extra months to live before you actively try to cause the end of the world."

Jonathan's eyes snapped back to hers. "Three months."

"That's how long I estimate it will take for the heavenly fire to dissipate from your body." He was hunting out lies in her words as he considered. Just as she anticipated, but he hadn't asked her anything she needed to lie outright about... yet.

And you would let me leave afterward?" A superficial question. She doubted he would believe her answer. "Yes. I would." Conditional on whether she succeeded, of course, she would be happy to let him walk.

"What happens if I don't agree?" he probed.

"Then I can't help you." This was the question she didn't want to think about. What if he didn't agree? What if this didn't work? What would she do then? She didn't relish the idea of sitting back and letting someone die….. But if it was him or the world….Could she bathe her hands in his blood? She had never killed anyone before. She didn't want to start now. "I will have to sedate you, drop you off in a remote area where you couldn't hurt anyone, with enough food and water to last you the day-and-a-half you have left. After which, you will die a slow and painful death by the heavenly fire's purification."

The wheels were turning in Jonathan's mind as he stared down at the bedspread. Serena waited patiently. She made sure her voice didn't waver and her expression didn't falter while she described what she would allegedly do if he refused. He needed to believe she would do it. Even if it was reluctantly.

"Alright." He turned to her with a steely look. "I agree to your terms."

Serena didn't hide the smile from her face and mentally jumped for joy. A verbal agreement. That was a start. She clapped her hands together. "Excellent!" She exclaimed and jumped to her feet. She bounced out of the room and picked up a long, thin, polished wooden box and a leather folder of papers sitting on a sofa table against the wall outside of the door. When she returned and Jonathan saw what was in her hands, he frowned. Serena guessed he was expecting a key for his restraints. Ha. As if she would be that gullible.

She flipped open the leather folder and dropped it in his lap. "Now all you have to do is sign this and the chains will come off!"

Jonathan studied the first sheet of the multi-page document. There were runes around the edges of the page - each of the pages, in fact. "You want me to sign a written contract?"

"Duh. Do you, honestly, think I will take your word that you will keep our agreement?" His frown deepened and his eyes flitted to her before falling back to her contract. That was likely exactly what he thought – or hoped. "This" she pointed at the folder of pages, "will ensure that you follow the rules."

"This is quite long for a simple promise to do no harm." he stated evenly. The chains clinking on his wrists were just long enough for him to turn the pages. He flipped through them, giving each a cursory glance before moving on to the next.

"Oh, it's much more than that." Serena settled back in her chair. "It states that you cannot harm or convince, trick, or hire someone else to harm others. It describes, in detail what 'harm' means, and in case you were wondering it doesn't _just_ mean kill. It also states that you cannot contact your followers or associates through _any_ form of communication."

"And what if _I_ am attacked? There are a lot of people who want me dead. Am I supposed to let it happen?" he demanded.

"Obviously, you are allowed to defend yourself or others." She sighed. "And it isn't all about you, you know. There is also a section stating that this contract will terminate at the end of three months or in the event that either one of us dies. There is another section that says I will not alter the agreement after it has been signed."

Serena turned the folder to her and flipped to the last page. From her pocket in her dress she pulled out a small bottle of yellow liquid and uncorked it. She set the bottle on the end table with one hand and flipped the latch on the wooden box with the other. Lifting open the lid revealed two crystal quills. Serena picked up one and, carefully, pressed the sharp point into the pad of her thumb. Serena winced and a bead of blood formed where the quill punctured her skin. With blood on the tip of the quill Serena placed it on the first signature line and signed her name. Serena poured a few drops of the yellow potion on a bit of cloth and wiped the cloth across her thumb. The puncture mark was gone.

Jonathan turned the folder back to face him. He read the last few lines. "'If this contract is breached by either party, the offending party's blood will boil in his/her veins.'' Jonathan looked at Serena with raised eyebrows. "That's a little cliché, don't you think?"

Serena grinned and shrugged. "Why mess with the classics? They're called that for a reason. I thought it appropriate." She held out the box with the second quill. To get him to sign, she wrote this contract with fairness in mind. If he was the only one bound by it there was the possibility he may choose to test her resolve to dump him somewhere rather than help him. By including herself in the deal - as well as the consequences - she hoped it would dissolve any suspicion that this was a trap. And by explicitly providing a time limit to the deal he could see there was a proverbial 'light at the end of the tunnel'.

She tried to keep her nervousness from showing. This was it. If he signed the contract she would have all the time she needed to see what the heavenly fire would do. She honestly didn't know what the final outcome would be. Would it have too much or too little of an effect? The heavenly fire could burn out too soon and not purify him enough. It was possible it would be too aggressive and there would be nothing left of his mind in the end. Or it could do nothing at all since her potion was interfering. There were too many possible ways for this to fail.

Jonathan slowly reached for the quill and imitated her motions. With the blood on the tip he was about to put quill to page when Serena grabbed his hand. "You will sign your _real_ name." She instructed with an intense stare before releasing his hand.

Serena watched him place the tip on the page and scrawl out 'Jonathan Morgenstern' in an elegant script. The moment he lifted the quill from the page the runes on the page melted away and Serena felt a tingling sensation on the back of her right hand. The runes from the page were now on back of the hand she used to sign. They formed a ring and were enclosed in a circle on the inside and outside. In the center was an image of a crystal shard that appeared to be melting into a potion bottle. This represented the contract holder: Serena.

* * *

Sebastian silently examined an identical mark on the back of his own hand. "Don't worry. It will vanish when the contract is up." The witch assured him. He watched intently as she carried the jars and water back to the counter and picked up a small crystal key. Returning to his bedside she wrapped her left hand around his wrist to steady it and inserted the key. She turned the key and the lock released with a satisfying click. She proceeded to his other arm.

With the shackles gone Sebastian absentmindedly massaged his wrists. "So….what happens now, Miss Witch?"

"It's Serena. And….well, I can get you something to eat. You haven't had much in the last few days. Also, I imagine you don't want to spend three months sleeping in my infirmary and I don't mind moving you to the guest room…" She swept her gaze from the top of his head to the tips of his toes and back. "We'll have to shop for some clothes, too."

Sebastian threw off the covers and dropped his feet to the floor. He pushed slowly to his feet and the girl, who was directly in front of him, was forced to take two steps back. Sebastian stood half a head taller than her. He stared down at her and watched with mild interest as her eye changed to a darker shade of violet.

"Food then." Having received no answer from him, the witch made the decision herself. She turned on her heels and walked briskly out into the living area. Sebastian followed slowly, his limbs stiff from inactivity and confinement. "I'll warn you now," she called over her shoulder as she headed for the front of the room to the kitchen. "I'm a vegetarian."

She rounded the island counter, opened a cupboard below, and came up with a large salad bowl. "So if you want meat and such, you'll have to ask for it."

Sebastian carefully sat on the bar stool opposite her and watched as she scurried back and forth retrieving ingredients for what Sebastian guessed was some kind of oriental salad. He smirked, "What? You're not going to convert me?"

The girl gave a little smile while she peeled a mandarin orange. "One of my best friends is a werewolf. Converting you would seem a bit hypocritical, don't you think? Anyway, if you feel like making something, there's a portable grill in the cupboard at the end here, seasonings are in the overhead cabinet next to the refrigerator, dishes are also in the overhead cabinets, and the silverware is in the drawer left of the sink."

Sebastian casually surveyed the room. It was just as he remembered it from yesterday, but now there was a large pile of books on floor in front of the bookshelf. "The guest room is through the door at the bottom of the stair." she informed him. That was one of the doors he wasn't able to open last time, he remembered. "It has its own full bath, so you and I don't have to share. My room is through the door at the other end of the room." Door number two he couldn't open. The only mystery door left was the one at the top of the stairs.

"The second floor is off limits."

Sebastian's head snapped back around. "Why?"

Serena studied him shrewdly. "Don't get excited. I keep the more dangerous ingredients upstairs and there is no reason for you to be up there messing with my potion equipment."

Sebastian leans forward, resting his forearms on granite counter. 'What, exactly do you expect me to do over the next three months? This place doesn't appear to have a lot to occupy -"

"Someone like you?" She cut him off. "You could come with me on my visits, if you like."

"What do you do?" He doubted it would interest him.

"I travel the world, giving medicinal aid to Downworlders and have a few shops selling medicinal potions and remedies to anyone who needs them."

"You're suggesting I follow you around like some kind of pet while you play Healer-of-the-World?" he asked with disgust.

The witch paused in her mixing and rested her palms on the edge of the counter. "Like you said, there isn't much for you to do in this place. I thought you would like to come with me, but if you prefer to stay here and read my books or stare at the walls all day that's your prerogative."

"I don't find it entertaining to travel the world listening to people whining all day, either."

"Because listening to _your_ whining is _so_ much less annoying, Jonathan." She shot back, sarcastically. She dished out equal portions of the salad into bowls and shoved one in front of him.

"Sebastian." he corrected as she handed him a fork.

"Huh?" She paused and looked up. Each had an arm outstretched with a light grip on the utensil.

"My name is Sebastian." He repeated, tugging the fork out of her hand.

He watched her questioning look turn dark. "No," she replied with venom, "it isn't, _Jonathan_." She stabbed a little too hard with her fork at the greens in her bowl. _What was her problem?_ He frowned and they ate their meal in silence.

Later that afternoon his 'host' unsealed the guestroom door and he moved his belongings into what was to be his space for the next three months. The room was nothing special. It had all the basic furniture and little else: a single size bed, a nightstand with a lamp, and a chair by the window. There was a small closet for clothes and next to that was the door leading to his private bathroom.

Only a few hours had passed since he woke up, but already he felt weak and tired. He stretched out on the bed and heaved a sigh. _Wasn't the girl's concoction supposed to stop this?_ He turned his head to stare at the closed door that separated him from the annoying caregiver. She thought she was clever in getting him to sign that contract. The truth was it made little difference. He didn't have the Infernal Cup with him when he came here, his Endarkened did. Whether he was there or not they could continue moving forward with his plans. With Lilith's guidance they would grow his army and when his confinement ended all would be ready for the next phase of his plan.

So she could have her contract, drag him across the world, or call him whatever name she wished. In the end it wouldn't matter.


End file.
